Better header editor and added completion data

src-web/lib/data/headerNames.ts

@@ -0,0 +1,35 @@
+export const headerNames = [
+  'Content-Type',
+  'Content-Length',
+  'Accept',
+  'Accept-Charset',
+  'Accept-Encoding',
+  'Accept-Language',
+  'Accept-Datetime',
+  'Authorization',
+  'Cache-Control',
+  'Cookie',
+  'Connection',
+  'Content-MD5',
+  'Date',
+  'Expect',
+  'Forwarded',
+  'From',
+  'Host',
+  'If-Match',
+  'If-Modified-Since',
+  'If-None-Match',
+  'If-Range',
+  'If-Unmodified-Since',
+  'Max-Forwards',
+  'Origin',
+  'Pragma',
+  'Proxy-Authorization',
+  'Range',
+  'Referer',
+  'TE',
+  'User-Agent',
+  'Upgrade',
+  'Via',
+  'Warning',
+];